I like the before screenshot better, the before table covers the whole monitor.
Thats true, but the whole point is to get the dimensions of the table as close to original design as possible when changing from 16:9 to 16:10. Right now im playing with some of the "conversion" techniques as changing the x-scale for 4:3 tables to get to 16:9 or 16:10.
Its interesting to see that when i first convert your table to 4:3 (by setting x-scale to 2) and then to 16:10 the picture fills the entire screen too but looks a bit wide.

feels like there is some error in how we convert will experiment a little more. How are the initial x-scale and y-scale calculated?
but back on topic Daffy Duck is another fine table and 16:9 or 16:10 on a 16:10 monitor look definitely better than 4:3. Any hint how i can try to add the lockbar myself?
It was simple math until they added Layback, Layback stretches the table vertically and throws the simple math out of the window for trying to achieve a true vertical math perspective. When you look at the above screenshot, the bumpers don't appear round (not your fault) they appear to be wide, so if you think the table is too wide, then just make the Xscale a smaller number and use your eyes (rather than math) to make the table thinner.
I also have a wall on this table on the table side of the editor that is 800 units high (screenshot attached). I use this wall to push the table up or down like an overhead camera. This is how I can keep the xScale at 1.5 for WS or 2.0 for 4x3 res for any table dimension I've released lately. I adjust the height of this wall (higher number like 900 shrinks the whole table and a Lower number like 300 would zoom in on the table). I do this to get a top view of the flippers, which I like, so it is a different approach than the other table creators. We all make the tables a little different, so there are no miracle numbers that will work for every table.
If you want a lockbar, you would just add a wall to the front of the table, add a lockbar image (export one from any table), create a decal, set it to the surface of your new wall. It seems most players now want the table to cover as much of the monitor as possible vertically, so most of us have quit using lockbars and just zoom the table to fill the screen.
I don't mind explaining how I do something or how to do something with
VP. I'm not writing a tutorial on anything, but specific questions on how to do one thing are always welcome as long as it is specific. I also only help in threads, not PM's as then maybe someone else will be helped. It is easy to help someone who is actually using the editor, rather than the person who just asks, "How do you convert a table to Full Screen?" I mean, where do you start to even answer a question like that?